Florida's Supreme Court has upheld a lower court decision to throw out an award for damages of $145bn (£82bn) against major tobacco companies.
The firms were accused of failing to warn smokers of health risks
The award had been the largest ever by an American jury, but the court said on Thursday it was "clearly excessive".
Shares in the five cigarette firms involved rose after the ruling.
A jury awarded the damages in 2000 when anti-smoking campaigners brought a class action lawsuit, arguing the firms failed to issue strong enough warnings.
But the high court said in Thursday's ruling that making such an award would "result in an unlawful crippling of the defendant companies".
The court also approved a lower court ruling that it had been a mistake to certify a class-action lawsuit representing an estimated 300,000 to 700,000 Florida residents suffering from smoking-related illnesses.
The certification led to the huge jury award for punitive damages.
Large-scale actions are potentially more damaging than individual lawsuits.
The Supreme Court reinstated awards to a number of smoking-related cancer sufferers who brought the original suit.
The five firms in the case are Philip Morris, RJ Reynolds, Lorillard Tobacco of Loews Corp, Brown & Williamson, which is owned by British American Tobacco, and Liggett, which is part of Vector Group.
They successfully appealed to reduce the damages in 2003.